2026-08-18 九州大学
図1. 経済成長とCO2排出量の関係の推移過程（2000–2021年）
＜関連情報＞
- https://www.kyushu-u.ac.jp/ja/researches/view/1552
- https://www.sciencedirect.com/science/article/abs/pii/S092180092600265X
世界経済におけるデカップリング移行パターン：多地域構造分解分析 Decoupling transition patterns in the global economy: A multi-regional structural decomposition analysis
Waka Nishifuji, Shigemi Kagawa
Ecological Economics Available online: 27 July 2026
DOI:https://doi.org/10.1016/j.ecolecon.2026.109180
Highlights
- A transition-based decoupling framework with endogenous thresholds was developed.
- Thirteen global decoupling pathways were identified across 56 economies.
- Countries with similar decoupling states often followed different transition paths.
- Trade structures and consumption patterns drove divergent decoupling transitions.
Abstract
This study revisits the decoupling of economic growth and carbon emissions by identifying limitations in conventional state-based classifications and proposing a transition-based framework with endogenously determined thresholds. We use the global multi-regional input–output database (2000−2021) to construct continuous attribute vectors in order to capture the relationship between changes in per capita gross domestic expenditure (GDE) and per capita carbon footprints across 56 countries. Hierarchical clustering reveals seven distinct decoupling transition patterns. The results demonstrate that widely used fixed thresholds such as Tapio’s 0.8 boundary between coupling and weak decoupling may separate countries with highly similar trajectories while grouping countries that follow fundamentally different transition paths. Structural decomposition analysis indicates that, although improvements in emission intensity constitute the largest emission-reduction effect and per capita GDE growth remains the dominant driver of emission increases, divergent decoupling outcomes among countries with comparable growth rates are explained primarily by differences in trade structures and shifts in the sectoral composition of final demand. These findings suggest that decoupling should be understood as a development stage-dependent transition process rather than a static state, with important implications for structurally differentiated climate policy design.
